[英]How can i add var item in EF?
我有一個數組,其長度未指定。 也許100,110,...
對於每個值我都有:
int a1 = array[0];
var r1 = from row in db.products
where row.id == a1
select row;
int a2 = array[1];
var r2 = from row in db.products
where row.id == a2
select row;
...
如何獲得(r1 + r2 + r3 + ...(=和))的總和?
總結之后,我想序列化:
string s1 = js.Serialize(sum);
您可以在代碼中執行此操作:
表:
--use your db
USE [Breaz]
GO
/****** Object: Table [dbo].[theProducts] Script Date: 5/8/2017 3:49:33 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[theProducts](
[theId] [int] IDENTITY(1,1) NOT NULL,
[id] [int] NULL,
CONSTRAINT [PK_theProducts] PRIMARY KEY CLUSTERED
(
[theId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
SET IDENTITY_INSERT [dbo].[theProducts] ON
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (1, 5)
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (2, 6)
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (3, 7)
GO
SET IDENTITY_INSERT [dbo].[theProducts] OFF
GO
程序:
//use your database dbcontext
using (BreazEntities21 db = new BreazEntities21())
{
int[] a1 = { 5, 6 };
var r1 = (from row in db.theProducts
where a1.Contains((int)row.id)
select row).ToList();
int[] a2 = { 7 };
var r2 = (from row in db.theProducts
where a2.Contains((int)row.id)
select row).ToList();
var mergedList = r1.Union(r2).ToList();
var summation = mergedList.Sum(r => r.id);
var s1 = new JavaScriptSerializer().Serialize(summation);
}
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